American Mineralogist, Volume 59, pages 1330-1332, 1974 NEWMINERAL NAMES MrcnnBr,FrsrscHrn Allemontite Analyses are given of 2 samples from Tuka, the first con- Discredited;see Stibarsen. (B. F. Leonard) taining vesuvianite, the second small amounts of gehlenite, vesuvianite, and hydrogrossular. The X-ray powder data are Atheneite* given for Tuka and Carneal material. Tbe strongest lines given) A. M. Crenr, A. J. Cnronre, eNo E. E. FB.rBn (1974) (16 are, respectively, Palladium arsenide-antimonides from ltabira. Minas 211 310 222 Gerais, Brazil. Mineral. Mag. 39, S2B-543. Tuka 3.60 90 2.786 r00 2.547 30 pd Electron microprobe analyses of 2 grains gave 66.0, Carneal 3.60 100 2.787 100 2.545 20 65.6;Cu 0.1, 0.1; Hs 14.9,16.1; Au 0.5, 0.3; As 19.0,19.0; Sb 0.1, 0.3; sum 100.6, 101.4 percent, corresponding (av.) 321 411.330 440 (Pdzo to Cuoo'Hgo*) (Asr*Sbor), or (pd,Hg)" As. Tuka 2.345 34 2.O79 40 1.559 50 The mineral is hexagonal, space group p6/mmm, a 6.799, Carneal 2.38(b) 2.081 - 30 1.558 40 c 3.483 A,Z 2, G. calc 10.16, meas 10.2. The strongest X-ray lines (48 given) are 2.423 (vvs) (1lzt), 2.246 (vs) The a edge equals 8.829 (Tuka), 8.82 (Carneal), 8.837 (202r), 1.87r (ms) QllD, r.37r (s) (2132),1.302 (synthetic "gehlenite hydrate", Ca"Al,SiOz.H,O); Carlson (s)(3032),1.259 (s) ezSD, t.034(ms), GrS2\. (1964), who first synthesizedit, gave a 8.83 A. In reflected light white with a yellowish creamy hue, Hydrothermal experiments showed the gehlenite-bicchu- shows very weak reflectance pleochroism in oil, none in lite boundary to be at 635 J- 5'C, I kbar and at 595 r- 5.C, air. The mineral does not extinguish under crossed polars, 3000 bars. The mineral from Carneal is colorless, isotropic, -r showing bright anisotropic colors from purple-brown to n 1.625 (n of synthetic 7.628, Carlson, 1964). Sp. gr. - dark gray. Microbardness (2 grains), 419, 442, av. 431. synthetic 2.75 meas, 2.813 calc from unit cell data. Reflectancesare given for 2 grains in air and oil; av. values The name is for Bicchu, the type locality in Japan. Type Rr and R,: 470 nm, 47.47, 52.97; 546 nm, 51.08, 56.19; material is at Okayama University, Okayama, Japan, and 589 nm, 53.19, 58.14; 650 nm, 55.35, 59.95 percent. at the Institute of Geological Sciences, I-ondon. The mineral was found as a few grains in residual con- Bomertieite* centrates from gold washings at ltabira, Brazil. Intergrowths with arsenopalladinite occur, and hematite inclusions are A. M. Clem, A. J. Cnroorn, AND E. E. Fp.ren (1974) present. The name is "in oblique reference to its palladium Palladium arsenide-antimonides from Itabira. Minas content," the name palladium having been derived from the Gerais, Brazil. Mineral. Mag. 39, 528-543. name of the Greek goddess Pallas Athene, Type material is Electron microprobe analysesof 4 grains gave (range and at the British Museum. av.): Pd 71.96-72.90,72.4;Cl 0.93-1.13,1.1; As 10.74- Bicchulite* 10.99, lO.9; Sb 15.41-15.74,15.6, sum (of av.) 100.0 per- cent, correspondingto (PdnoCuo'") (As'.onShe), or (Pd,Cu)s Cnryoro HeNrvrr, Iseo KusecHr, KrrrNosure HENMT, p. A. (As,Sb)c, the same formula as mertieite (Am. Mineral SS, SearNe, .lNo B. R. YouNc (1973) A new mineral bicchu- Lra, I97t). lite, the natural analogue of gehlenite hydrate, from X-ray study shows the mineral to be cubic, space group Tuka, Okayama Prefecture, Japan, and Carneal, County Fd 3m, a 12.283A, Z = 16, G calc 10.33, not measured. Antrim, Northern Ireland. Mineral..t. (Tokyo) 7, 24j_ The strolrgest lines (49 given) 2.356 (vs) 333,511, 251. are 2.167(ws) 440,1.533 (ms) 800, 1.253(ms) 844,0.860 (s) The mineral was found and reported almost simultane- 10.10.2,14.2.2, 0.821 (s) 12.8.4,0.800(s) 10.10.6,14.6.2, ously to the I.M.A. Commission by groups in Japan and 0.788 (s) 999, l1Jl,I, and others,0.780 (s) 12.10.2, England. The mineral occurs in skarns at Tuka, town of 14.6.4. Bicchu, Okayama Frefecture, associated with vesuvianite In reflected light pale yellow-white; 3 of 5 grairis studied with or without hydrogrossular, gehlenite, and calcite, also were anisotropic in shades of dull brown, brighter in oil. in skarns at Carneal, Northern Ireland, associatedwith hy- Reflectances are given in air and oil; mean for R, and Rz drogrossular and melilite in a bufi-colored coating on wolla- in air: 47Onm, 45.23, 45.66; 546 nm, 52.67,52.88; 589 nm, stonite-rock. 55.82, 55.93;650 nm, 58.80, 58.E2 percent. Vickers hard- ness, 587-597, av. 592 (100 load), 585-598,av. 591 * e. Minerals marked with an asterisk after the name were (50 g. load). approved before publication by the Commission on New The mineral occurs as grains 0.4 to 0.8 mm in size in Minerals and Mineral Names of the International Miner- concentrates from gold washings at Itabira, Brazil. alogical Association. In one grain it was intergrown with arsenopalladinite, 1330 NEW MINERAL NAMES 1331 which was free of hematite inclusions present in the iso- rose. Optically biaxial; the sign changesat 638 nm in sam- mertieite. ple l, 112 nm sample 2, 596 nm sample 3. Microhardness The name is in allusion to the relation of the composition 360-400, av. 380 kg/sq mm with 50g load. Reflectanceswere to that of mertieite.Type material is at the British Museum. measured for 3 samples at 15 wave lenglhs (440-740 nm), including the following for R'p and R'g: 460 nm; no. 1, Killalaite* 41.8, 42.8; no. 2, 49.0, 51.2; no. 3, 45.0, 46.5 percent, R. Newez (1974) Killalaite, a new mineral from Co. Sligo, 540 nm, no. l, 45.4, 48.6; no. 2, 53.8, 56.6; no. 3, 50.6, Ireland. Minerol. Mag. 39, 544-548. 52.2 percent 660 nm, no. l;56.0, 55.0; no. 2,57.9,59.2; no. 3, 61.8, 58.9 percent. Electron microprobe analysis, using synthetic augite as The mineral occurs in copper-nickel sulfide ores of the standard, gave CaO 57.0 -{- I, SiO, 39.8 -t- 1, HeO (by Talnakh ore field, in cubanite-chalcopyrite, difference 3.2 percent, corresponding to CasSi,O'' l/2 H,O Oktyabr deposit, and cubanite-mooihoekite ores. It oc- (theory CaO 56.6, SiO, 40.4, H,O 3.0 percent). MgO, Fe,Oe, cubanite-talnakhite, curs as polysynthetically twinned grains, commonly inter- and Al,O" were (0.I and microchemical tests for CO, and grown with sperrylite, native Ag,. Pd Bi, and (Pt,Pd)sSn. F were negative: The mineral gives HrO when heated in a Palladium Olouo closed tube. The name is for the composition, I (-Tin), preserved at the Fersman Min- The strongestX-ray lines (47 given) are 3.03 80, 2.824 Type material is Geology, Moscow. lA0,2.724 ffi, 2.275 45,2.224 45, 1.41340. Assuming d = eralogical Museum, and the Institute of 2.88 (calc from ns) and p 105', approximate unit cell di- Stibarsen mensions were calculated to be a 9.3, b 9.9, c 7.7 A (all -+0.1A). The IMA Commission on New Minerals and Mineral The mineral occurs as crystals up to 2 mm long, cleavages Names has acceptedby a vote of 1l-1 the name stibarsen {100} perfect, also {010} and {001} good. Monoclinic. for the single-phase hexagonal As-Sb mineral whose com- Complex penetrative twinning with composition plane in- position is essentially AsSb (M. Fleischer, written com- cluding the b axis, yielding cross "bow-tie" twins. Optically munication to B. F. Leonard, May 14, 1974). The Com- biaxial, neg., ru (Na) a 1.635, t 1.642 (both +-'0.002), mission recognizesallemontite as an intergrowth of stibarsen 2Y - 26",Y - b,ZAc - 16'. with either arsenic or antimony and rejects the name The mineral occurs near Inishcrone, Killala Bay, Ireland, allemontiteas a synonymfor stibarsen. in a limestone thermally metamorphosed by a basalt- B. F. LroNeno dolerite dike. It occurs, associatedwith calcite or afwillite, and replacing tilleyite, in spurrite-rich rocks; scawtite, Tantal-aeschynite* [-Tantal-aeschynite'(Y)] cuspidine, and xonotlite are also present. M. S. Aousuurlll, C. Krcrt, eNo E. A. J. Bunre (1974) The name is for the locality. Type material is at the Ulster Tantal-aeschynite, a new mineral of the aeschynite group Museum, Belfast, and the British Museum of Natural His- from the Borborema region, north-eastern Brazil. Mineral. tory, London, Maq.39,571-576. Paolovite* Analysis by electron microprobe by C.K' gave TazOo 6.2, La,Os l'3, A. D. GeNrtN, T, L. EvsrrcNrevl, L. N. Vyelsov, I. P. 39.3,Nb,os 18.7,TiO, 11.7,Fe,Or 0.9, CaO 0.6, Gd,O' 0.6' LltutrNe, eNp N, V. GnoNBvl (1974) Paolovite,Pd, Sn, Ce"O" 3,7, PrrO, 0.6, Nd,Os 1.9, Sm,O" Y,O' 4'6, ThO, 6.5' UO, a new mineral from copper-nickel sulfide ores. Geol. DyrO, 0.4, Er,O, 0.4, YbrO' 0.7, 0.4, sum 98.5, correspondingto the formula (Cao*(Y,Ce)o n* Rudn.